WebSphere® Application Server monitors thread activity and performs diagnostic actions if one has become inactive.
WSVR0605W: Thread threadname has been active for hangtime and may be hung. There are totalthreads threads in total in the server that may be hung.where: threadname is the name that appears in a JVM thread dump, hangtime gives an approximation of how long the thread has been active and totalthreads gives an overall assessment of the system threads.
WSVR0606W: Thread threadname was previously reported to be hung but has completed. It was active for approximately hangtime. There are totalthreads threads in total in the server that still may be hung.where threadname is the name that appears in a JVM thread dump, hangtime gives an approximation of how long the thread has been active and totalthreads gives an overall assessment of the system threads.
WSVR0607W: Too many thread hangs have been falsely reported. The hang threshold is now being set to thresholdtime.where: thresholdtime is the time (in seconds) in which a thread can be active before it is considered hung.
You can prevent WebSphere Application Server from automatically adjusting the hang time threshold. See Configuring the hang detection policy
UTLS0008W: The alarm thread threadname has been active for n milliseconds and may be hung. totalthreadsthreadstack
In this message, threadname is the name that appears in a JVM thread dump, n is approximately how long the thread was active, totalthreads is an overall assessment of the system threads, and threadstack is the exception stack of the thread.
If the alarm work eventually completes, the following message is written to the system log. This message indicates thread that produced the false alarm.
UTLS0009W: Alarm Thread threadname was previously reported to be hung but has completed. It was active for approximately n milliseconds.
In this message, threadname is the name that appears in a JVM thread dump, and n is approximately how long the thread was active.
Typically, system alarms do not process heavy loads because such activity might slow the processing of later system alarms, which in turn might impact server behavior. The UTLS0008W message is intended to help IBM Support personnel investigate problems potentially caused by system alarm behavior.
All of the system alarms share a common alarm thread pool. The properties which govern the monitoring of this thread pool can be tuned using the administrative console. You can reduce the frequency at which WebSphere generates alarm hung thread messages by adjusting the alarm thread monitor check interval or threshold. See the topic Configuring the hang detection policy for a description of how to change these settings.